Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 221732

Area Forecast Discussion
National Weather Service Topeka KS
1132 AM CST Wed Feb 22 2017

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 318 AM CST Wed Feb 22 2017

Early this morning the region was under relatively zonal mid-level
flow, with water vapor imagery showing a few embedded waves over
Colorado and western KS, which was helping to usher some high clouds
into north central KS.  Surface obs showed a surface trough
stretching north to south across central KS early this morning, with
southerly winds across the CWA expected to keep temperatures nearly
steady through sunrise before quickly rising through the day. Models
show a weak cold front tracking eastward into central KS this
morning and bisecting the CWA by early afternoon before stalling out
over east central KS this evening.  No precipitation is expected
with this frontal passage, but the southerly flow ahead of this
boundary will support strong warm-air advection to result in another
day of near-record high temperatures with highs generally in the
mid/upper 70s. The "coolest" readings are expected across north
central KS where winds will shift to the northwest behind the
morning frontal passage.  Model soundings show very dry air in place
today with the boundary layer mixing up to around 800-850mb. As a
result, some of the stronger winds aloft may mix down to the
surface, resulting in winds gusting to 15-25mph with the higher
gusts focused across far east central and far north central KS. The
combination of dry conditions and gusty winds will result in Very
High Fire Danger conditions across the entire CWA today.  See the
Fire Weather section below for more details.

By tonight, a surface low will move into southwest KS with the
lingering frontal boundary stretching into east central KS.  With
this approaching surface low, expect increasing mid/high clouds
overnight into Thursday.  This cloud cover will keep overnight
temperatures mild once again with lows only dropping into the mid

.LONG TERM...(Thursday through Tuesday)
Issued at 318 AM CST Wed Feb 22 2017

On Thursday, models move an upper level trough out into the Plains.
A surface low initially over southeast Colorado is forecast to move
northeast while a warm front extends eastward across the CWA. Within
the warm sector a rather stout EML develops across the area which
will inhibit convection for much of the day. Forecast soundings show
the cap eroding toward the 23Z time period and with increasing lift,
shear and instability present will keep thunderstorms for the
evening hours. The track of the surface still has some spread with
the NAM and GFS further north than the ECMWF. They are not too far
apart and will go with a blend of the solutions for the official
forecast. Initially thermal profiles are warm enough for all rain in
the far north along the Nebraska border Thursday evening then cool
enough after 06Z for a mix of rain and snow. By Friday morning the
upper low will be located om eastern Nebraska with the surface low
in southwest Iowa. As the system pulls to the northeast during the
day a mix of precipitation will be possible across the far north
within the deformation zone, however the heaviest precipitation will
be located north in Nebraska. Friday evening the thermal profile
will favor all snow, however accumulating snow is expected to remain
north of the CWA. Temperatures Thursday will be in the 60s to mid
70s, then cooling off into the 30s Friday night behind the cold
front. Temperatures for Friday will range from the upper 30s in
north central Kansas to the lower 50s southeast of I-35. A zonal
flow sets up for the weekend, with shortwaves streaming out across
the Plains. Model continue struggle with the timing of the waves so
confidence is not very high with precipitation chances Sunday night
and Friday. Forecast soundings show light snow possible Sunday night
then changing back over to all rain on Monday. Rain chances will
continue through Tuesday morning southeast of I-35. Highs Saturday
will be in the 40s with temperatures warming back into the 50s and
60s Monday and Tuesday.


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1129 AM CST Wed Feb 22 2017

VFR conditions are expected throughout the period. Winds will
continue to veer the northwest throughout the afternoon, although
decreasing below 10 knots this afternoon. The shifting winds will
continue into Thursday as easterly winds increase by 14Z with
sustained 10-15 knots and gusts near 20 knots. Scattered rain
showers are expected to overspread the area Thursday morning. Any
lingering shower is expected to exit the terminals near the end of
the period.


Issued at 318 AM CST Wed Feb 22 2017

Dry conditions were already in place across the region this morning,
and with model soundings showing dry air aloft, dewpoints will
remain low today in the 30s. With model soundings showing the
boundary layer mixing up to 800-850mb, some of the stronger winds
aloft may mix down to the surface with winds gusting 15-25 mph.  As
the weak cold front becomes stalled out over eastern KS this
afternoon, the higher wind speeds are expected on either side of
this boundary (i.e., across far east central KS and far north
central KS). The wind direction will shift from southwest to
west/northwest today with the eastward-moving front.  These
southerly winds will aid in near-record high temperatures again
today with readings in the mid/upper 70s. As a result, RH values are
expected to drop into the low/mid 20 percent range.  These RH values
combined with some gusty winds will result in Very High Fire Danger
conditions this afternoon across the entire CWA.  However, models
show these wind gusts beginning to diminish just as the RH`s bottom
out this afternoon, so the higher wind gusts may not coincide with
the timing of the lower RHs.  As a result, have decided to not issue
any Fire Weather headlines at this time, but will continue to
closely monitor conditions today.


Issued at 318 CST Wed Feb 22 2017

Record Highest Maximum Temperatures:

...for Today February 22...

Topeka......74, set in 1995
Concordia...76, set in 1982




SHORT TERM...Hennecke
CLIMATE...Hennecke/53 is the U.S. government's official web portal to all federal, state and local government web resources and services.